Internal grinding machine



R. A. QUIMBY INTERNAL GRINDING MACHINE Jan. 7,1958

5 Sheets-Sheet 1 Filed July 18. 195s INVEN TOR. RALPH A. QUIMBY Iih'oaugvs Jan. 7, 1958 .Filed July 18. 1956 R. A. QUIMBY 2,818,687

INTERNAL GRINDING MACHINE 3 Sheets-Sheet 2 INVENTOR. I RALPH A. QUIMBYATTO RN EYS R. A. QUIMBY INTERNAL GRINDING MACHINE Jan. 7, 1958 3Sheets-Sheet '3 Filed July 18, 1956 INVENTOR/ RALPH A. QUIMBY- BY 0M,(5m

ATTOR N EYS INTERNAL MA 2 Application July 18, 1956, Serial No. 598,580

8 (Llainrsa (Cl. 51-95) This invention relates to internal grindingmachines and particularly to work sizing of a round workpiece which issupported by an outer peripheral surface and an end surface while beingrotated and while the rotating abrading tool is being applied to aninternal surface.

This application is a continuation-in-part of application Serial No.354,197, filed May 11, 1953 issued as U. S. Letters Patent No.2,758,427, dated August 14, 1956.

In the said co-pending application means are shown and described forprecisely supporting a rotating workpiece on a fixed axis by supportmeans in contact with an outer peripheral surface of the workpiece whilethe grinding tool is being applied to the internal surface. Alsodescribed and shown as associated with the peripheral surface supportmeans is a rotating backplate positioned with respect to the peripheralsupport means so as to make contact with an end face of the rotatingworkpiece and against which the workpiece is urged by pressure meanssuch as a pair of rolls in contact with the opposite end of theworkpiece. The backplate together with its associated pressure meanstherefore acts to position the workpiece in an axial direction to keepit on the peripheral support.

In such machines it is desirable to rotate the workpiece by driving thebackplate, the rotative force being imparted to the workpiece byfrictional contact of the backplate. It is necessary to cause theworkpiece to be urged against its peripheral support and one such methodis to position the backplate on an axis which is eccentric to thesupport determined axis of the workpiece and in a relationship to itsuch that rotation of the backplate not only drives the workpiece butalso urges it radially against the peripheral support.

In such a machine the most accurate means for sizing the workpiece forcompletion of the finishing operation is to gage the work and adesirable type of gage to use for finished work sizing is a plug gagewhich enters the work when the hole formed by the internal surface beingground has been sufllciently enlarged by the finish grinding operation.

Since it is necessary to mount the plug gage concentric with the supportdetermined axis of the workpiece and since the plug gage has to bemounted on the same side of the workpiece as the backplate because ofthe fact that the grinding tool is applied to the workpiece from theopposite end it has been found necessary in prior machines also to mountthe backplate concentric with the support determined axis of theworkpiece so that the plug gage could be supported within the backplate.Such an arrangement thereby loses the advantage of mounting thebackplate eccentric to the support determined axis of the workpiece.

Accordingly it is the object of the present invention to providemechanism for supporting and rotating a plug gage concentric to thesupport determined axis of the workpiece in combination with means forsupporting and rotating a backplate eccentric to the support determinedatent O axis of the workpiece, in order to obtain the advantages of theuse of an eccentric backplate while using a plug gage.

An embodiment of the invention is herein described in connection withthe drawings in which:

Fig. 1 is an elevation view partly in section of the part of an internalgrinding machine which embodies the invention.

Fig. 2 is a top plan view of part of the mechanism shown in Fig. 1together with a drive motor and associated mechanism.

Fig. 3 is a view from the right-hand end of Fig. 1 taken along the lines33 thereof.

Fig. 4 is a top plan view of part of the mechanism shown in Fig. 3.

In the drawings a work head indicated at A supports a workpiece W havingan internal surface S, and an abrading tool T is supported on a toolhead B for introduction into the workpiece W and application to theinternal surface S. The work head A is supported on a traverse table 10which is slidable on a base 12 and in a V-way 11 to the left and rightas viewed in Fig. 1 to move the grinding wheel T relatively in and outof the work for loading work and truing the wheel T and forreciprocating the wheel T back and forth across the surface S duringgrinding.

The wheelhead B is slidable on Ways 13 on the base 12 in a directiontransverse to the movement of the table 10 to feed the tool T againstthe workpiece surface S by suitable feed mechanism indicated at 15.

The traverse table 10 is actuated to the left and right by suitablemechanism which may be fluid pressure means including a piston 17connected to the table 10 and operating in a cylinder 18. Fluid pressureis alternately supplied and exhausted to and from the cylinder 18through fluid lines 19 and 20, a pressure line 21 and exhaust lines 22and 23 and controlled by a valve 25 having a plunger 26 actuated toreverse the flow of fluid pressure to the cylinder 18 by an arm 31pivoted at 32 and connected at 33 to a plunger rod 34. For oscillationof the tool T across the surface S during grinding the arm 31 isoscillated by a pair of dogs 38 and 39 attached to the table 10. The dog39 is pivoted at 40 and is lifted out of the Way to allow the table 10to run out to the left at the completion of grinding by a solenoid 42having a plunger 43 whose upper portion 44 makes contact to raise thedog 39 when the solenoid 42 is energized by suitable gage operatedcontrol mechanism not shown. After the traverse table 10 has been movedout to the left to run the tool out of the work for reloading andtruing, the table 10 may be run back into the work by operation of ahandle 30 on the arm 31.

The workpiece W as best seen in Fig. 3 is supported on a fixedsupport-determined axis by a peripheral work support indicated at whichmay include arcuate shoe elements 51, 52 and 53. The support shoes 51and 52 may be fixed and the support shoe 53 may be pivoted at 54 andlocked in position during grinding by a reed 55 held against movement bya fluid pressure piston 56 as more particularly described and claimed insaid co pending application Serial No. 354,197 issued as U. S. LettersPatent No. 2,758,427 dated August 14, 1956. The support elements 51, 52and 53 make contact with the external peripheral surface P of theworkpiece W. The workpiece W is thus held immovable radially while thetool T is being fed to the right as seen in Fig. 3 against the internalsurface of the workpiece.

To hold the workpiece W on its peripheral support 50, a circularbackplate 60 is positioned with respect to the support 50 so as to makecontact with one end e of the workpiece W and a pair of rolls 62 and 63carried on a yoke 65 pivotally mounted at 66 are urged against theopposite end e of the workpiece to force the workpiece against thebackplate 60. The outer end 67 of the yoke 65 is urged outwardly, i. e.,downwardly as viewed in Fig. 4, by fluid pressure means including apiston 68 operating in a cylinder 69 to urge the rolls 62 and 63 againstthe workpiece.

The backplate 60 is carried on a hollow spindle 70 which is rotatablymounted in bearings 72 and 73 supported on an upward extension 74 of thetraverse table 10. The backplate 66 is mounted with its axis eccentricto the support-determined axis of the workpiece W. The eccentricity isexaggerated and for clarity is shown in the plane of the paper inFig. 1. The plane of the eccentricity is best seen in Fig. 3. Thus whenthe backplate 60 is rotated in a clockwise direction as seen in Fig. 3it not only drives the workpiece W by reason of its frictionalengagement therewith but also exerts a component of force on theworkpiece W tending to drive it downwardly against the peripheralsupport 50.

The backplate 69 is driven by an electric motor 3%) through a belt 81and a pulley 82 mounted on the lefthand end of the backplate spindle 70.

A plug gage 85 is mounted concentric to the supportdetermined axis ofthe workpiece W and therefore eccentric to the axis of the backplate 6tand is carried on a gage spindle 86 extending through the hollowbackplate spindle 70 and the backplate 60. The spindle 86 is slidableand rotatable in a sleeve 88 fixed in an upper extension 89 of the tablethereby forming a cantilever support for the gage 85. The gage 85 isalso rotated by the motor 80 as seen in Fig. 2 through a belt 949 and apulley 91 fixed on the rear end of the gage spindle 86.

During reciprocation of the grinding tool T across the surface S of theworkpiece W the gage 85 is also reciprocated relative to the workpieceand thereby kept clear of the tool T by means of a longitudinallyslidable rod 95 seen in Fig. 1 whose right-hand end 96 makes abuttingcontact with an abutment face 97 on the base 12 moving the rod 95relatively to the left as the traverse table 10 moves to the right. Anupwardly extending arm 10-!) mounted on the left-hand end of the rod 95makes contact with the outer non-rotatable portion 101 of a hearing 102whose inner portion 103 is carried axially immovably relative to thegage spindle 86 between a shoulder 105 formed by a reduced portion 106of the spindle and the pulley 91. A pair of springs 110 and 111 extendbetween the outer bearing portion 101 and the upwardly extending pluggage mount 89 and urge the spindle 86 and gage 85 to the right towardthe workpiece W so that reciprocation of the gage 85 is caused by therod 95 in one direction and by the springs 110 and 111 in the oppositedirection.

Suitable means such as arm 115 pivoted at 116 is provided for actuationby movement of the gage into the work when the work has reached apredetermined size, and a switch 118 closed by the arm when the arm ismoved in a counterclockwise direction by contact of the outer bearingmember N11. to stop the feed of the wheel relative to the workpiecesurface S and to withdraw the wheel from the work.

It will thus be seen that the present invention provides means by whicha plug gage may be mounted concentric to the workpiece and eccentric toa blackplate on the same end of the work-piece eccentric to theworkpiece.

I claim:

1. In an internal grinding machine, means to support a workpiece forrotation on a support-determined axis, a hollow backplate arranged inproximity to said support means to make contact with one end of saidworkpiece, means including a hollow spindle rotatably to support saidbackplate on an axis eccentric to the said supportdetermined axis, agage extending through said backplate and a bearing member supportingsaid gage on an axis concentric with said support determined axis.

2. In the combination as set forth in claim 1, said bearing memberextending at least part way through said hollow spindle.

3. In the combination as set forth in claim 1, said bearing memberaxially slidably supporting said gage.

4. in the combination as set forth in claim 1, said bearing memberrotatably supporting said gage.

5. In the combination as set forth in claim 4, means to rotate saidgage.

6. In the combination as set forth in claim 1, said gage being rotatablysupported by said bearing member and means to rotate said backplate andsaid gage.

7. In the combination as set forth in claim 6, a driving connectionbetween said backplate and said gage.

8. In the combination as set forth in claim 1, a grinding toolapplicable to a said workpiece in said support means, means toreciprocate the grinding tool relative to the backplate axially of thebackplate to pass the tool back and forth across the face of theworkpiece, and means to reciprocate the gage axially of the backplate intime with the said movement of the tool to keep the gage clear of thetool.

References Cited in the file of this patent UNITED STATES PATENTS2,771,714 Schmidt Nov. 27, 1956

